1. Field of the Invention
The present invention concerns a band, which is in particular looped around a stationary body and around an object to be suspended, which is provided with a series of impressions spaced at uniform distances from each other, which appear on the front side of the band as elevations, and on the rear side as depressions, whereby the elevations have a part with an external wall extending perpendicularly to the surface of the band, and the depressions, on the rear side of the band, have a part with an internal wall extending perpendicularly to the surface of the band, in such a way that all the parts of the elevations which are oriented perpendicularly to the surface of the band fit in a form-locking manner into the parts of the depressions which are oriented perpendicularly to the surface of the band.
In particular, the band serves for the suspension of pipes, cables (which are laid down, for example, in a U-shaped channel), air conduits, and underslung surfaces.
2. Description of the Prior Art
Different bands which are specially formed for such purposes, such as, for example, perforated bands and bands which are provided with impressions, are already known. Perforated bands have the disadvantage that they are weakened by the perforation. There are different types of bands which are provided with impressions; for example, such as have the impressions formed so that they can slide over one another in a ratchet-like manner. Bands of this type serve for drawing bundles or bales together. They are less well suited for purposes of suspension. Furthermore, bands are known which are only provided on the ends with impressions with a different form. Such bands are, however, unsuitable for purposes of suspension.
One known type of suspension band taught by Swiss Pat. No. 435,881 is provided with a stamped serration extending over the entire length of the band, which is so shaped that the elevations on the forward side of the band can engage in a form-locking manner into the depressions on the rear side of the band. When using this band for purposes of suspension, the overlapping band ends must be held together by means of a coupling unit. The sides of the stamped serration do extend relatively steeply, but are not perpendicular to the surface of the band. The traction force acting in the longitudinal direction of the band is transferred from one end of the band to the other end of the band with the aid of the serration. Because of the inclination of the serration surfaces of the surface of the band, there arises a component which proceeds perpendicularly to the surface of the band, which has the tendency to loosen the form-locking connection. This force component requires a solid coupling so that it can hold the ends of the band together. The stamped serration proceeding laterally to the band extends over a considerable portion of the width. Through this, not only is the tensile strength of the band reduced, but the stamping also has a consequence that the band easily breaks during severe bendings.
These problems were solved by the band of the applicant in accordance with Swiss Pat. No. 608,287, and this band has indeed proven itself in actual practice. However, its manufacture has presented a number of problems. In particular, the shoulder in the elevations and depressions led to a materials flow, which led to structural changes in the crystal lattice of the metal, which in turn caused brittleness. This further led to cracks or to hair-line cracks, and thus to losses in production.